#include <stdio.h>
void main()
{
	float mu = 1;
	float sum = 0;
	int flag = 1;
	float pi = 0;
	for (mu = 1; 1 / mu > 0.0001; mu += 2)
	{
		sum = sum + flag / mu;
		flag = -flag;
	}
	pi = 4 * sum;
	printf("pi=%f",pi);

}